Access to most purchasable miracles/covenant miracles is tied to story progress and exhausting dialogue with the right people, but that'll be explained as we go along. Also worth noting, a lot of miracles can be bought with a massive discount from Rhea. So if you're short on souls, most of Petrus' stock can be gotten from Rhea instead, being 75-90% cheaper.
A little checklist how to trigger Rhea of Thorolund's store;
- Talk to Petrus after completing the tutorial
- Kill the Bell Gargoyles and come back to Firelink, Rhea of Thorolund, Vince and Nico will be standing near Petrus. Exhaust all their dialogue including Petrus' and carry on with your game.
- Progress down the Tomb of the Giants, you'll stumble upon a fellow called Patches the Hyena near the first bonfire, he'll push you down the loot-riddled hole where Rhea will be sitting on a mound of bones. Talk to her and kill Vince and Nico who are nearby.
- Talk to her again after killing them, get the reward and carry on the quest to murder Mr. Nito.
- After Nito's death,
be absolutely sure to go speak with Rhea at her new location near the altar in the Undead Parish, where the Firekeeper Soul once was. If you change locations twice after killing Nito without talking to Rhea or as much as clear a single one, she'll be killed by Petrus and all you'll find is a Pendant and some humanity, locking her store for good on the current playthrough.
PURCHASED------------------------------------
HEAL -
4000 souls, Petrus of Thorolund/1000 souls, Rhea of ThorolundEither gotten if you started out as a Cleric or bought from Petrus/Rhea. Petrus is on the patio near the elevators to the Undead Parish. Rhea's near the Firekeeper's Soul loot location up in the Parish.
GREAT HEAL EXCERPT -
10000 souls, Petrus of ThorolundRather pointless little spell sold by our dear old friend Petrus.
GREAT HEAL -
10000 souls, Rhea of ThorolundThe full version of Petrus'.
HOMEWARD -
8000 souls, Petrus of Thorolund/1000 souls, Rhea of ThorolundFantastic spell and also another example of just how appreciative Rhea is to your heroism. Hell of a discount.
SEEK GUIDANCE -
2000 souls, Petrus of Thorolund/500 souls, Rhea of ThorolundNeat little spell that makes more orange soapstone and summon signs pop up, which again is heavily discounted by Rhea late in the game.
FORCE -
4000 souls, Petrus of Thorolund/1000 souls, Rhea of ThorolundAlso pretty cheap at Rhea.
WRATH OF THE GODS -
10000 souls, Rhea of ThorolundUnique spell from Rhea that's considered the melee PvPers bane.
MAGIC BARRIER -
6000 souls, Rhea of ThorolundLast unique spell from Rhea you can purchase. If you bought all spells from her and cleared her stock, she'll move out to the Dukes' Archives where she sadly turns hollow and hostile in one of the crystallized cells.
KARMIC JUSTICE -
40000 souls, Oswald of CarimThe odd t-posed floating guy that appears after you ring the Undead Parish church bell sells this spell, can't miss him on your way down from the ladders.
REWARDED FROM NPCS------------------------------------
REPLENISHMENT -
Rhea of Thorolund, Tomb of the GiantsIf you've followed the checklist at the top there, you should find Rhea in the pit in the Tomb of the Giants. She'll ask you to kill Nico and Vince who've gone hollow. After doing so, she'll reward you with this miracle.
EMIT FORCE -
Siegmeyer of Catarina, Anor LondoThe way to trigger this guy's appearances is by first chatting to him near the closed gate to Sen's Fortress. This is optional but, hey, better be sure, right?
Once you got access to Sen's, there's a bit where you have to run up a set of stairs at the bottom and go through a fog wall near the top, while boulders are rolling down said stairs. Fall off the edge on the right, you should fall on a ledge where he'll be sitting quietly. Kill the two Serpent Soldiers, and exhaust his dialogue there again. Be sure to turn the machine so the boulders shoot out into the forest on your way up.
After your journey through most of Anor Londo and you got into the castle, you'll find him another time in yet another bit of peril, on the second floor of the castle in one of the bedrooms he's trapped in by a bunch of Silver Knights in the adjacent room - Kill them for him and talk to him again, he'll give you a Tiny Being's Ring and you're free to carry on.
Next time you're in Firelink Shrine, he'll be at the bonfire, chat with him and he'll give you the miracle.
FOUND IN THE WORLD------------------------------------
BOUNTIFUL SUNLIGHT -
Duke's Archives, JailIn the jail area of the Duke's Archives, there's a bunch of pisaca's that'll become hostile upon you leaving your cell. Way down at the bottom near Logan's holding cell, there's two dormant ones that won't attack or even retaliate; These drop both Bountiful Sunlight and Soothing Sunlight.
SOOTHING SUNLIGHT -
Duke's Archives, JailFrom the other dormant pisaca near the bottom of the jail area.
GREAT MAGIC BARRIER -
Ash LakeThis little pesky bastard is tucked away in the big hollowed out tree in the Ash Lake, go up the branch and fall down the one that's poking out the side, it's a little risky but once you fall, just follow the tunnel and you can't miss it.
A little video for reference, considering this one is just... Who the hell would've guessed that you gotta fall down?TRANQUIL WALK OF PEACE -
CatacombsNear the second bonfire, after you cross over the bridge, there's two skeletons near a rickety looking wall. This wall can be busted down, head through and try to not be murdered by the skeleton archers and their giant skeleton pal, grab the loot from the open casket behind him(You'll need it later), go into the hallway on the right side facing the casket, follow it all the way down and head up the ladder after killing the necromancer - It'll be on a grave not far away from the ladder.
VOW OF SILENCE -
Painted World of AriamisNow this one requires a fair bit of work; First you'll have to gain access to the Painted World by retrieving the Peculiar Doll from the Undead Asylum which can be gotten back into by first falling off the elevators onto a little platform, jumping to the adjacent pillars, going up the spiral stairs and finally kneeling down in the birds nest at the very top. The doll will be in your cell, the very one you started the game in.
Once that's done, go to Anor Londo, specifically the massive ballroom with the give or take fifteen Painting Guardians, "touch" the massive snowy painting on the far wall and you'll be there.
Now you gonna find your way down into the sewers below the Painted World, just progress as you normally would through the zone and once you're in the sewers; Bust down the gray rather stony looking walls, at the end of this semi-maze will be a corpse with the Annex Key. Head back up and go into the church-like area on the right from the Phalanxes, go upstairs and to the rooftop where the miracle will be on a corpse. Beware, on pick-up, about four Crow Demons will ambush you.
SUNLIGHT BLADE -
Anor Londo, Darkmoon TombDon't get this one before getting the covenant reward from Gwyndolin, the Darkmoon Blade miracle.
After defeating Gwyndolin down in the Darkmoon Tombs area of Anor Londo(
accessed by wearing the Darkmoon Seance Ring that you found in the casket on your way to the Tranquil Walk of Peace miracle, at the very bottom of the rotating stairs in early Anor Londo), it's in one of the chests at the end of the hallway with the other goodies.
COVENANT REWARDS------------------------------------
GRAVELORD SWORD DANCE -
Gravelord CovenantAwarded upon joining the Gravelord covenant, down in the Catacombs. Just make sure you haven't killed Nito yet, for obvious reasons. He won't be as much of a charming leader once you're trying to murder him for his soul, after all.
Anyway, be sure to grab the Eye of Death behind the Prowling Demon in the long dark hallway a fair bit past the second bonfire of the area, escape the Prowling Demon and lie down in the interactable tomb with the lid half off a bit infront of the Demon(Don't worry, he'll remain dormant 'til you take a few more steps closer). About a minute later you'll be in Nito's domain. Join his covenant and wham, it's yours.
GRAVELORD GREATSWORD DANCE -
Gravelord Covenant, +1Now you gotta get to rank one with the covenant, which takes ten Eyes of Death. You should already have the three I told you to grab from behind the Prowling Demon, so that leaves seven to go which luckily can be easily farmed from Basilisks in the Great Hollow, especially with the Golden Serpent Ring. Just be sure not to get cursed, so be safe and buy a few Purging Stones.
DARKMOON BLADE -
Blade of the Darkmoon, +1The one could take you forever to obtain... First you have to retrace the steps to get access to the Painted World, as explained on Vow of Silence and farm the Crow Demons over and over with 10 humanity on your counter and a Golden Serpent Ring and get 10 Souvenir of Reprisals.
Next up is getting the ring I've mentioned before, the Darkmoon Seance Ring. Follow the information on Tranquil Walk of Peace to figure out where it is.
Now head to Anor Londo, hit the spiral staircase and turn it to go down. Equip the ring and head down to the foggate past the bonfire,
do not go through the fog however, a voice will tell you to halt and kneel down at the red carpet with the candles; This is your way into the covenant. Give the souvenirs and all done, if you desire you can go ahead and murder the leader now by going through the fog gate and grab Sunlight Blade after the battle.
LIGHTNING SPEAR -
Warrior of SunlightFirst of all, you'll need 25 Faith to join this one. Either that or a reduced amount which is decided by how many white phantoms(coop hosts in this case) you've assisted previously, which lowers the number by five for every person helped by your hand. So if you've helped three people, the requirement's only 10 Faith. Jolly cooperation!
In order to get this you'll still have to get into the Warriors of Sunlight, which is located at the Undead Parish. A simple and easy way to get there is to head up the bridge with the Hellkite Dragon and stand in one of the two alcoves to the sides and wait give or take 10 seconds. He'll come down to try and kick your ass mano-a-mano.
Instead of fighting him, bolt through his legs the second he lands. He'll always do this frontal cone fire breath attack upon landing so this is your best chance; Run into the little room with the bonfire and sit the hell down, the Dragon resets and flies away for the time being(until your next visit atleast) if you try to leave through the front exit.
The little door to the right leads to a overlook with a destroyed altar, that's the place you wanna be at.
GREAT LIGHTNING SPEAR -
Warrior of Sunlight, +1And then came the time consuming part. Now you'll have to get ten Sunlight Medals and rank up in the covenant. One's given for everytime a boss is killed, regardless of host or coop partner, for as long as one is a part of this covenant. So supposedly you can just get this by helping ten people out on any given boss that allows summons.
If you summon Solaire to any of the boss fights that allow him to help and he survives the ordeal, you'll also get one.
Other sources are;
- 3 are found in a chest opposite from the bonfire room in the Anor Londo castle.
- 1 is given to you after you chat to Lautrec of Carim in Firelink, after saving him from his cell in the Undead Parish before killing the Gargoyles. Another is dropped if you proceed to murder him after he gives this reward.
- Very rarely, the Chaos Bugs in the shortcut to Lost Izalith drop them too.
SUNLIGHT SPEAR -
Warrior of Sunlight, +1Oh jolly cooperation, you'll need rank one in the covenant and the Soul of Gwyn, Lord of Cinder - The very last boss of the game. So this is the only reason why this achievement is simply unobtainable until new game plus. You won't have to rank up another time in any new game plus so that saves time on that front, at least. Once you make it back to the altar, you'll have a new option saying "Offer Lord Soul" which rewards this miracle.